Sahebjami, who lives in a state where voters overwhelmingly supported Hillary Clinton, said she knew many who disapproved of Trump’s vulgar language.

Children “don’t know anything about the issues, like manufacturing jobs,” she said in a phone interview with The Washington Post. “But they know — at least where I live, it’s really prevalent [for kids] to say, ‘Oh, he’s the mean one.’ ”

The idea started with her own son, a kindergarten student who said he was concerned about things Trump had said about Muslims, because the family has relatives of Iranian descent.

“So I said to him, ‘Well maybe we should write a letter to him and we can show him,’ ” Sahebjami said. “ ‘Why don’t you talk to him about why it’s important to be kind?’ ”

She added: “It was very simplistic, at a 5-year-old level, where I started.”

Her son’s letter, which he dictated to Sahebjami, read: “Dear President-elect Trump, please be a good president. Be kind to all people. Some people in my family are a special religion and they are not bad guys.”

A Facebook group was created encouraging children to write letters to President-elect Donald Trump "about the importance of being kind to other people, even if they're different than you are." Here are some of the messages children had for Trump. (Monica Akhtar/The Washington Post)

Spurred by this, Sahebjami consulted with friends who have children about posting such letters in a private, online group.

“This is an opportunity to seize and teach our children how to be articulate, productive communicators,” Sahebjami said.

However, she emphasized that she wanted the Facebook group to be a “multi-partisan, global grass-roots campaign” that offers parents a chance to turn a divisive election into a “teachable moment.”

The rules were simple: Letters must be written by children under 18.

They should be positive, nonpartisan and kind in tone.

“It’s great if kids can tell their own story, and how this issue is important to them personally,” Sahebjami wrote on Facebook. “… Consider this as your opportunity to persuade.”

She encouraged parents to take pictures of their children’s letters and share them on social media using the hashtag #kidsletterstotrump.

“The power of this movement comes from the kindness and unity we can teach our children,” Sahebjami wrote. “This isn’t about policies — it’s about high standards of basic human kindness that ALL parents can get behind.”

Sahebjami said the Facebook group is a closed one, to maintain a positive environment. But it has grown quickly in part because any member can add a new member.

“We chose to make it a closed group so that our children would be protected to some extent,” she said. “I have denied two neo-Nazis so far. Where obviously there’s going to be hate, that’s not welcome here on this site. But people of all parties who have articulate, compelling things to say are welcome.”

Gradually, the letters from children trickled in.

Some messages were only a few words.

“DEAR MR TRUMP Be kind please FROM A Littel Boy TOMMY,” read one, underneath a drawing of a rainbow.

“Dear Mr. President, be nice to things. Do not say mean things. This helps me calm down: meditation, reading and resting,” wrote 6-year-old Szaba. “Good luck with your new job! Let me know if I can help.”

Her mother, Angela Hylland, thanked Sahebjami for organizing the group, saying it was an ideal outlet for their family.

“My daughter (6) has been buzzing with eagerness to get more involved in her community since the election, and this was a fun, positive way for her to get started,” Hylland wrote on Facebook. “She took it very seriously … down to making the outside of the letter colorful, so President-Elect Trump would be intrigued to open it.”

That girl was not the only child to offer Trump advice. Seven-year-old Kela drew up a 12-point checklist titled “How to be nice!”

To Mr Trump,

How to be nice!

1. Say kind things like well done

2. Don’t blame other people when it is you doing the bad thing

3. Don’t lie

4. Don’t scream at people

5. Behave

6. Don’t tell people what to do

7. Have nice manners like say thank you and no thank you

8. Listen to other people

9. Don’t talk meanly

10. Don’t hurt people

11. Help people

12. Being different is COOL!!!

Warm regards,

From Kela (in the UK)

Age 7

Still others referenced promises Trump had made during his campaign, such as deporting undocumented immigrants and getting Mexico to pay for a border wall.

“Dear Mr. Trump, Kids in my class are very scared. Please don’t kick them out. In my school we get sent to the wall when we’re in trouble. My friends did not do anything wrong. Don’t send them to the wall. Love, Abby age 6.”

“Dear Mr. Trump I won an award at school for kindness and respect. I think you should be kind and do not!! build a wall between Mexico and America. Because we have friends there. Please be kind. Sincerely Henry.”

Repeatedly, Sahebjami reminded people to keep it positive — and to mail their letters to Trump Tower so that the president-elect and his wife, Melania, might read them.

Sahebjami said she is hopeful that the letters from children would resonate with Trump, who is a father to 10-year-old Barron. The president-elect is also a grandfather.

“If he got bags and bags of letters from kids, he would see that those are everyday Americans who want to hold him to high standards of basic human kindness,” Sahebjami told ABC affiliate KATU. “I would hope that he would be affected by that.”